I guess in a sense. But the amount money is high that is crazy. OSRS bossing includes a constant potential with no rares of 3-4m per hour equating to 15-20m RS3. Reaching those amounts normally on RS3 is typically including those rares. So idk when I'd say osrs is p2w. I guess it's the potential since the grind is longer using the cases that are less. But as far as straight cover development, RS3 has it hands down. GE prices inform the story OSRS is cover to acquire BiS things than RS3. OSRS gamers are eager to shell out almost 7 times the true money to purchase the most expensive BiS equipment in OSRS BiS equipment themselves at 43, it is many times harder to grind.
Lamps mostly just give xp, but other than Skilling Hiscores, many RS3 progressions like MQC, RuneScores, Clue Hiscores and Reward Systems can not be bought with xp (and therefore lamps). Not sure I agree, after all abilities like RC can turn to buyables with treasure hunter. Some of the promos have been ridiculously to the point at which it is somewhat like a buyable skill. Although I suppose that is opting for 200m.
You will get more OSRS iinformation on https://www.winrsgold.com/